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Thursday, December 31, 2015

TOP 5: 2015

Yeah!, I like the top 5 ranking. And especially when there's that many things to choose that makes almost an impossible decision to pick just 5!
Without more preable, here they go!

5- Falcons
If in the Top 5 2014 I placed "Eagles" in the number 5, this year is the turn to Falcons. With the invasion of Red-footed Falcons (Falco vespertinus) during May in Catalunya, and the "Falcon story" that you may have already heard about, this year I have actually trapped and ringed Red-footed, Peregrine, Hobby and Merlin. A very nice combo!


4- Illa de l'Aire
During May I spent some days in Illa de l'Aire, an small island south of Menorca, in the Balearic Islands. As always, I had very nice days with an incredible company. Thanks, one more time, to all Menorcan friends and see you in 2016!!


3- Morocco
In February I went to Morocco, for some days ringing in Yasmina lake and some days birding around the country. It was my second time there, but I enjoyed everything again as it was the first time. As Bald Ibis was selected in the 2013's top 5, this the picture will be about a Temminck's Lark (Eremophila bilopha), that was really tame close to Boumalne Dades.


2- 3900 ringed birds!
I just checked the total number of birds I have ringed in Catalunya this year: more than 3900. That's an actual lot, considering the places where I usually go and the fact that I am usually alone!
Anyway, big thanks to all friends that have come in one or another session for their help!! I kind of think 4000 birds will be hard to reach, but let's see...
Some birds from this year (click to enlarge!):


1- Falsterbo
Falsterbo is still on the first position, for the third year already. A part from the Falcon story, many other things happened, and with very nice friends around. I could tell that many things, that I'll just leave it remembering this Yellow-browed Warbler (Phylloscopus inornatus). A big hug to all my friends and... Vi ses!!!



All the best for 2016, another very nice year is just ready to start...
Molt bon any nou!

Wednesday, December 30, 2015

December is over!

I am still without that time that I would spend writing some posts, so I am forced to write this review of the hole month of December, today is already 30th!

During the first weekend of December, and "keeping the tradition", already for 5 years, we went to the Ebre Delta. This year, probably because of the very soft temperatures and the lack of rain for many, many days, we had a curious mix of species. Indeed, we saw wintering Purple Heron (Ardea purpurea) and some Yellow Wagtails (Motacilla flava), and despite we had no wind and the sea was perfect to do some seawatching (and spot the traditional flock of Scoters), we weren't able to see any.

Squacco Herons (Ardeola ralloides) are regular but scarce
wintering species in the Ebre Delta.
As actual wintering interesting stuff, we saw 2 Black-throated Divers (Gavia arctica), 1 Brambling (Fringilla montifringilla), 1 Bittern (Botaurus stellaris), 1 Hen Harrier (Circus cyaneus), a minimum of 34 Jack Snipes (Lymnocryptes minimus) (which is a lot!), and the Pacific Golden Plover (Pluvialis fulva) that has been around for the last three years. But as I was saying, no Melanittas at all, and along the Trabucador sandbar, we only got to see 4 Red-breasted Mergansers (Mergus serrator). As I said I previous posts, this autumn-winter feels weird, vquite good for some species but inexplicably bad for others...

Scoters!!
No, of course not. A flock of Coots (Fuclica atra) on the sea...
This year we also spent quite a lot of time reading PVC rings, especially from Flamingo (Phoenicopterus roseus) and Glossy Ibis (Plegadis falcinellus).

Also a Great White Heron (Casmerodius albus) with a red
PVC ring. Any idea where it comes from?
We had the very nice visit of Timmy and his Maltese friends, that were on a Spanish-Catalan trip for a few days. It was very nice to see and do some birding with them!!

The Ebre Delta is a very special place. Sunset + flamingo flock is usual scene there, and always very nice and special.

And a video:

Dunlin (Calidris alpina) and Little Stint (Calidris minuta) flocks, on the
background of the video, were in usual numebers.

The weeks after I was quite busy, and the few free mornings I had I went out ringing around my usual places. It's already 4 years since I started the constant effort ringing station at La Corbatera, where I ring 7 times in summer and 3 in winter (one in December, one in January and the last in February). In this year's December seassion I got a lot of nice old retraps. Already in October I realised it was a good year for Blue Tits (Cyanistes caeruleus), and as I was expecting, I trapped some in the constant effort station. Seemingly they like a lot that area! The case is that among the Blue Tits I got, most of them were retraps, with individuals from a lot of different sessions, both in summer and winter. Two were more special than the others: one ringed as adult on 28/12/2012 (first ringing there), and a French retrap!!

I joined GACO friends while ringing Griffon Vultures (Gyps fulvus) and Great Cormorants (Phalacrocorax carbo) in two different days. Very nice to leave little passerines for one day and go for big stuff!

Back to passerines, I started ringing in a new place with small fields surrounded by Mediterranean Hackberries (Celtis australis), one of the favourite trees for many thruses and Hawfinches (Coccothraustes coccothraustes) here during winter. Indeed, we mainly trapped thrushes: Song Thrush (Turdus philomelos), Mistle Thrush (Turdus viscivorus) and Blackbird (Turdus merula), and two very nice Hawfinches as well!!

Adult (EURING 4) female.
The second, also adult female.
First-year (EURING 3) Mistle Thrush
For the ones with ID difficulties between Mistle and Song Thrushes, three pictures of both species together, hope it helps! viscivorus to the left and the one in the bottom in the belly picture, philomelos to the right.
 

We also went for another ringing session of Alpine Accentors (Prunella collaris). 4 more birds ringed!
Very tame species...!
To end with good purposes, the start of a new project: colour-ringing Rock Sparrows (Petronia petronia). On the drylands around my village it is usual to find flocks oh hundreds of Rock Sparrows, that is meant to be a regular but not very anundant breeder in the area. Many questions related to local movements are in my mind, and that's why I have decided to start ringing them with colour depending on the location. Let's see if it works!

Friday, December 4, 2015

Diverse ringing weekend

I am still quite busy with many things, which gives me almost no time to write. Last weekend I had a very nice and diverse captures.

Friday evening (yeah, let's consider it the start of the weekend already!), I did another session in the Reed Bunting (Emberiza schoenilcus) roosting. This year is clearly not as good as last season was in the whole area. Also, the proportion of adults seems to be unusually higher than previous seasons in this place and than I would expect. That might be consequence of the very bad breeding season, fact that we already noticed this summer in Falsterbo.

An interesting adult (EURING 6) male with white feathers on
crown. Maybe leucistic, maybe a result of the 'progressivegreying'!
Adult (EURING 6) Reed Bunting

During Saturday morning we did a new session in the Siskin (Spinus spinus) feeder. Results were, as it is becoming usual, more than great. This year, with two sessions done, we have already ringed more than 100 Siskins and retrapped about 20 individuals from last year. It was also remarkable the recovery of this first-year male from Lithuania!


Again, as I said about the Reed Buntings, the proportion of adults is unusually high! Probably for the same reason. Nonetheless, it is a very good year for Siskins in Catalunya!

I spent the afternoon in Montserrat mountain, for sure one of the most beautiful places in our country. In this singular mountain in the pre-litoral mountain chain, Alpine Accentors (Prunella collaris) are common wintering species, as well as Wallcreepers (Tichodroma muraria). Last year I started trapping Alpine Accentors in the highest tip, Sant Jeroni, where a tame flock is easy to spot during the whole winter.


Views from Sant Jeroni. Rocky slopes with mediterranean vegetation are the
wintering habitat of some Alpine Accentors.
On Sunday, and together with some of my very best friends, we went to La Fumera and we put some nets around the house, as we have been doing for 3 years. As always, some nice birds were trapped:

As I said, Siskins are pretty common this year. We got 20,
feeding on rural plant seeds. Adults male and female above.
It is also a quite good year for Goldcrests (Regulus regulus)!
Eurasian Jay (Garrulus glandarius) is always a nice species
to catch. In this case, an adult (EURING 4).
In three years of ringing in this place we already start to have some nice retraps. This Robin (Erithacus rubecula) was trapped two years ago, last year, and last weekend again.


Controls might be quite interesting in terms of ageing and sexing, cause then is when you can actually check things, as you have "age-proven" birds. We got 3 control Long-tailed Tits (Aegithalos caudatus), two from 2013 and one from 2014.
Head details of the three control Long-tailed Tits. The two
above were ringed in 2013, and the one in the bottom in 2013.
Note that the eye-lid colour is yellow in the three birds, a bit
more orangish in the one in th bottom.
I have heard many times that this might be reliable on ageing,
but other factors (related to the internal status of the bird) can
also be influent on the colouration of the eye-lid
(see Greig-Smith, P.W. (1984). Changes in the eye-lid of Long-tailed Tits);
so I am not 100% confortable ageing birds with yellow eye-lids as adults.
For me, it only would be useful during the breeding season (juveniles
seem to always have very dark-red eye-lids), but then, ageing on plumage
traits is even easier and reliable.
The "entire family". Long-tailed Tits are well known for the cooperative
breeding strategy. Summarizing, chicks from the first clutch help to raise their
brothers from the second clutch. After fledging, it's very easy to see them in
big family flocks. We can't be sure that the flock above was an entire family,
but they look like, don't they? ;)

Thursday, November 12, 2015

'Paradoxus' Black Redstart

I remember when I caught my first Black Redstart (Phoenicurus ochruros) and I read, in Svensson's:
"1Y male (two morphs; one rare, 'paradoxus', distinguisable); chin, throat and breast largely blackish with wide (buff-) grey tips, resembling ad. male but juvenile wing retained, lacking the withe 'panel' [...]"
"1Y female / 1Y male ('cairii' morph, common); as ad. female [...]"

The implication of these sentences is clear: only first winter male 'paradoxus' Black Redstarts will be possible to sex. But, what does a 'paradoxus' look like?

Breeding bird, carrying food for the chicks. Is it a male or a
female? Photo: Bernat Ferrer
Although I haven't been able to find any publication where both morphs are well-defined; what is said in the literature is that between 10-12 % of 1w males are 'paradoxus', even the concept is not fully defined. There's a Catalan project named "Cul Roig" where the proportion of 'paradoxus' was also studied, obtaining 10% as a result (www.phoenicurus.net).

The first explanation for the different morphs that come to my mind is related to competition and sexual selection. When a bird species is delaying the acquisition of the definitive colour and pattern of plumage until after the first potential breeding period it is referred to as having a delayed plumage maturation (Hawkins et al. 2012). Many hypothesis have been made and tested to explain DPM in Black Redstart, "Female or Juvenile Mimicry Hypothesis" being the mainly studied one, and not supported. As far as I could find, the explanation of DPM in Black Redstart remains uknown (Landmann & Kollinsky 1995, Kollinsky & Landmann 1996, Cucco & Malacarne 1999, Senar 2004, Schwarsová et al. 2010, Apfekbeck et al. 2012).

On 04/03/2015 I trapped three Black Redstarts in my usual ringing place. This wouldn't be noticeable, but two of them showed very interesting traits.


I saw the first bird from the distance and I quickly thought "what a nice adult male!". The actual excitement came when I realize it was not an adult!


This is probably a very typical 'paradoxus'. All moulted feathers are like they would be in an adult male.
Adult (EURING 4) male, to compare. Ageing 'paradoxus'
in the field can be quite easy!
The second bird I trapped was more intriguing. Postjuvenile feathers (body, head, lesser, median and 3 inner GCs) were greyish, a bit more intense and colder than a usual 1w Black Redstart, and more greyer than what I would expect on a 'cairii' male too. Some black feathers were hidden on the chin and breast. I sexed this bird as a male.


If a 'paradoxus' is a first winter male Black Redstart showing "male traits", this bird should definetely be considered of this morph. Thus, 'paradoxus' might include huge variation, depending on the two main factors: moult extension and "male-like" postjuvenile plumage degree.
The third that was trapped was also a 1w, looking like a 'normal' bird, either male or female.


Doing some research back home after that, I found these very interesting tips on sexing 1w ochruros in the very useful Ringer's DigiGuide. I don't know if this has been validated with retraps, but I believe it anyway. I will still be quite reluctant to sex 1w females on this feature because I think I might need more experiece if it's not clear. As it will be explained later, 1w males seem to show huge plumage variation, and as it is also commented on DigiGuide, "an unknown portion of post-juvenile male tertials does not seem to show the white edges"; so I don't feel comfortable sexing a female on this feature that some males could show too. What it is more clear to me is that if a first-year show any of this "faint male traits" (white edges on moulted tertials / SS, very grey body feathers or wing coverts) it should be safey sexed as a male.
Individuals still in juvenile plumage are not possible to sex.
First-year (EURING 3), unsexed. Body feathers are quite greyer,
could it be a 'cairii' male?
First-year (EURING 3), probable female. All tertials are
moulted, with brown edges. The entire plumage is brown-grey.
The Ringer's DigiGuide also refers to intermidiate morph individuals. As I said with that bird above, these intermidiate birds should be defined as 'paradoxus' too on the basis of the male traits they (already) show. It seems that 'paradoxus' has a huge variation, as I said before, depending on two factors: moult extension and the colouration of postjuvenile feathers.

First-year Black Redstarts moult head, body and all lesser and median coverts with very high frequency. From zero to all GCs are moulted; Jenni & Winkler (1994) found GC 10 and 9 replaced between 90-100% individuals, mean 3.5, mode 2 (n=477), while in Ottenby Bird Observatory they found an extension about 2 to 10 greater coverts (more than 60% of birds with 2-4 inner GCs moulted) (Ringer's DigiGuide data). Out of 66 moult chards in N Spain, 0-7 GCs were moulted; 90-100% renewed the 2 innermost and only 0-10% renewed GC4 and GC5; mean 3.2 (Roa et al. 2007).

Sadly I don't have enough data on moult extension from Catalunya, although my feeling is that most of 1st winter birds that I have trapped have moulted between 1 and 5 GCs. What I find especially interesting is that most of the 'paradoxus' that I have seen had quite extensive moults. For example, the first bird from March 2015 had 6 GCs and two tertials moulted.

The following bird was trapped at Falsterbo Bird Observatory during this autumn season. The extension of the moult is quite surprising, involving all greater coverts, carpal covert, all alula, tertials and 3 inner secondaries. As it sometimes happen with unusually extensive partial moults, there's some asymetry, with the second secondary and a primary covert moulted on the left wing only, and the middle alula feather unmoulted on the left wing as well.

Right wing. All GCs, alula, carpal covert, tertials and 3 inner secondaries are
moulted, as well all lesser and median coverts and the rest of body and head.
Left wing. S2 and a primary moulted are moulted only in this wing, and the
middle alula feather is unmoulted.
As it usually happen with most of males that are still browner on mantle
but 'paradoxus', moulted wing coverts are much more greyer and 
"adult-male-like". As it can be also appreciated in the first picture, the white
 wing panel is very extensive, because of the extensive moult involving 
tertials and inner SS.
Tail feathers also have an unusual amount of black close to the tip, maybe
related to the same reason of this bird being a 'paradoxus'?
All pictures by Josefina Pehrson.

Such intraspecific differences in the partial postjuvenile moult extension have been reported in other passerine species, and most of them are related to different populations with different biology, like different migration distances, etc., like most of Fringillidae species, with more extensive moults in S Europe. Individual quality has been also suggested to be very determinant to individual partial moult extension. With moult data from Sweden (Ottenby Bird Observatory, online), Switzerland (Jenni & Winkler 1994) and Catalonia (personal data), it seems there's no significant differences. What attracts my attention is that 'paradoxus' seem to have  more extesive postjuvenile moult in average. This difference could be especially related to individual quality, which I think could be determinant too to show "male traits" in the plumage (to be 'paradoxus'). First-year males with higher individual quality would be more prone to showing "male traits", and also a more extensive moult, while first-year males with poorer condition would be more similar (or identical) to females in plumage, and with a less extensive postjuvenile moult.

The two 'paradoxus' from March 2015
To me, this also suggests that we can expect an almost continous gradient between the two classical morphs, 'cairii' and 'paradoxus', from 1w males identical to 1w females (and therefore unsexable), to birds like the one above to the right. This gradient would include the full plumage: amount of dark feathers on body and head, white edges on tertials and secondaries (if moulted), grey colour on body feathers and moulted wing coverts, and so on.

Another example of variation, this first-year male that I trapped last week:
5 GCs moulted, also the middle tertial on the left wing. Mantle
feathers are bluish-grey, but black is restricted to face, throat
and breast, but not as black as the first bird from March.
Both birds (the one from March and this one) have the base
of the lower bill bright yellow coloured. Some but not all
adults show this feature... but we can leave this for another day.

Supporting the whole thing, it seems that levels of testosterone can have some influence when doing the postjuvenile moult, and determining the morph (Schwarzová et al. 2010). Testosterone levels can be determinant for different reproductive related things in birds. For instance, it's been proven that testosterone also affects song modulation in the Black Redstart (Apfelbeck et al. 2012).

More research is still needed to confirm many things about this morph. In the meantime, I encourage you to go out, find some, document and report them!

Acknowledgements
To Josefina Pehrson to review and improve the text and also let me use her pictures of the Falsterbo bird, and to Bernat Ferrer, who sent his picture of the breeding bird (it was actually a female!), and also for the help in many sessions were Black Redstarts have been caught.

References
- Apfelbeck, B., Kiefer, S., Mortega, K.G., Goymannm W. & Kipper, S. (2012). Testosterone Affects Song Modulation during Simulated Territorial Intrusions in Male Black Redstarts (Phoenicurus ochruros). PLoS ONE 7(12): 10.1371/annotation/89b74b56-3f48-4ee2-9da1-699b3fdea564
- Blasco-Zumeta, J. & Heinze, G.M. (online)331.Black Redstart. IberCaja Aula en Red, Obra Social IberCaja.
- Cramp, S. (ed.) (1988). Handbook of Birds of Europe, the Middle East and North Africa. Volume V. Oxford University Press, Oxford.
Cuadrado, M. (1995). Winter territoriality in migrant Black Redstarts Phoenicurus ochuros in the Mediterranean area. Bird Study 42:3, 232-239.
Cucco, M. & Malacarne, G. (1999)Is the song of Black Redstart males an honest signal of status? The Condor 101: 689-694
- Hawkins, G.L., Hill, G.E. & Mercadante, A. (2012). Delayed plumage maturation and delayed reproductive investment in birds. Biological Reviews 87, 257-274.
- Jenni, L. & Winkler, R. (1994). Moult and Ageing of European Passerines. Academic Press, London.
Kollinsky, C. & Landmann, A. (1996)Altitudinal distribution of male Black Redstarts: are there age-dependent patterns? Bird Study 43:1, 103-107.
Landmann, A. & Kollinsky, C. (1995). Territory Defence in Black Redstarts, Phoenicurus ochruros: Effects of Intruder and Owner Age? Ethology 101:2, 121-129
Nicolai, B., Schmidt, C. & Schmidt, F-U. (1996)Gediederkmale, MaBe und Alterskennzeichen des Hausrotschwanzes Phoenicurus ochruros. Limicola 10: 1-41
- Ottenby Bird Observatory (2015). Ringer's DigiGuide - Phoenicurus ochruros. www.ringersdigiguide.ottenby.se
Roa, I., Colino, J.M., Rodríguez Martínez, N. & Arroyo, P. (2007). Biometría y Extensión de la muda parcial de Phoenicurus ochruros en la provincia de León. Jornadas Ornitológicas Cantábricas. Oseja de Sajambre (León), 12-14 Octubre de 2007.
- Schwarzová, L., Fuchs, R. & Frynta, D. (2010). Delayed plumage maturation correlated with testosterone levels in Black Redstart Phoenicurus ochruros males. Acta Ornithologica 45(1): 91-97.
- Senar, J.C. (2004). Mucho más que plumas. Monografies del Museu de Ciències Naturals 2, Museu de Ciències Naturals, Institut de Cultura, Ajuntament de Barcelona.
- Societat Catalana d'Anellament (online)Projecte "Cul Roig".
- Svensson, L. (1992). Identification Guide to European Passerines. Fourth Edition. Lars Svensson, Stockholm.